Fluorescence Cubes - Fast Blue & WU

The photomicrograph below illustrates the nerve cell tracing reagent Fast Blue in a retrograde labeling experiment using the WU fluorescence cube. The excitation spectrum of Fast Blue crosses over into the emission spectrum, as illustrated below with the green spectra.

Objective: APO 40X
Photoeyepiece: PE 3.3X
Fluorescence Cube: WU
Exposure Mode: SFL 30